Increased circulating adiponectin in males with chronic HCV hepatitis

Liver and serum adiponectin levels in non-alcoholic fatty liver disease

OBJECTIVE

Adiponectin is an adipokine that has anti-steatotic, anti-inflammatory and anti-fibrotic effects. The impact of these different activities impact on the development and progression of non-alcoholic fatty liver disease (NAFLD) is not well understood. The aim of this study was to evaluate both liver and serum adiponectin levels in patients with and without NAFLD and determine any clinical correlations.

METHODS

Liver tissue and serum samples were collected from patients undergoing liver biopsy between April 2014 and July 2020, and categorized based on histopathological diagnosis into hepatic steatosis (HS), non-alcoholic steatohepatitis (NASH), and hepatitis control (HC). A Luminex xMAP assay was performed on both liver and serum samples to measure adiponectin levels. Statistical analysis compared liver adiponectin (LA) and serum adiponectin (SA) levels between groups.

RESULTS

A total of 48 participants were included in the analysis. The mean LA level was lowest in the HS group, followed by the NASH group and the HC group (P = 0.036). The mean SA level was 3.61 μg/mL for the NAFLD group and was significantly lower than that in the HC (7.51 μg/mL; P = 0.001).

CONCLUSION

Adiponectin levels are lower in NAFLD compared to HC in both serum and liver tissue. LA levels in patients with HS were significantly lower than in both the NASH and HC groups, suggesting that adiponectin is related to inflammation in the liver and probably reflects its role in the pathogenesis of NAFLD.

Roles of Adipokines in Digestive Diseases: Markers of Inflammation, Metabolic Alteration and Disease Progression

Adipose tissue is a highly dynamic endocrine tissue and constitutes a central node in the interorgan crosstalk network through adipokines, which cause pleiotropic effects, including the modulation of angiogenesis, metabolism, and inflammation. Specifically, digestive cancers grow anatomically near adipose tissue. During their interaction with cancer cells, adipocytes are reprogrammed into cancer-associated adipocytes and secrete adipokines to affect tumor cells. Moreover, the liver is the central metabolic hub. Adipose tissue and the liver cooperatively regulate whole-body energy homeostasis via adipokines. Obesity, the excessive accumulation of adipose tissue due to hyperplasia and hypertrophy, is currently considered a global epidemic and is related to low-grade systemic inflammation characterized by altered adipokine regulation. Obesity-related digestive diseases, including gastroesophageal reflux disease, Barrett's esophagus, esophageal cancer, colon polyps and cancer, non-alcoholic fatty liver disease, viral hepatitis-related diseases, cholelithiasis, gallbladder cancer, cholangiocarcinoma, pancreatic cancer, and diabetes, might cause specific alterations in adipokine profiles. These patterns and associated bases potentially contribute to the identification of prognostic biomarkers and therapeutic approaches for the associated digestive diseases. This review highlights important findings about altered adipokine profiles relevant to digestive diseases, including hepatic, pancreatic, gastrointestinal, and biliary tract diseases, with a perspective on clinical implications and mechanistic explorations.

Adiponectin levels and insulin resistance among patients with chronic hepatitis C

Chronic hepatitis C virus (HCV) infection is associated with insulin resistance (IR), rapid disease progression, and decreased virological response to antiviral treatment. In addition, obesity is a risk factor for chronic hepatitis C evolution and is associated with IR. As adiponectin is an adipokine that is associated with obesity and IR, this study aimed to investigate serum levels of adiponectin among patients with HCV infection and IR. Thirty-three patients with untreated HCV infection underwent testing of serum adiponectin levels (capture ELISA) and were compared to 30 healthy subjects with similar body mass indexes (BMI). Data were also obtained for several homeostatic model assessment (HOMA) indexes: HOMA-IR, HOMA-β, and HOMA-adiponectin. Patients with HCV infection had higher adiponectin levels, which predominantly were observed among women. Hyperadiponectinemia was not associated with high BMI. Patients with HCV infection had higher HOMA-IR and HOMA-β values, although no difference was observed for HOMA-adiponectin. Patients with HCV infection and overweight/obese status had higher HOMA-IR values, although no association was observed for adiponectin levels. Hyperadiponectinemia and IR were not influenced by HCV load or liver fibrosis. The predictors of IR were BMI, glycemia, and serum levels of insulin and non-high-density lipoprotein cholesterol, but not adiponectin levels. Thus, patients with chronic hepatitis C have significant metabolic alterations (hyperadiponectinemia and high HOMA-IR values) that are independent of HCV viremia and liver fibrosis. Among these patients, HOMA-IR but not HOMA-adiponectin was appropriate for diagnosing IR.

The evolving relationship between adiponectin and insulin sensitivity in hepatitis C patients during viral clearance

BACKGROUND

The evolution of the relationship between adiponectin and insulin sensitivity in hepatitis C virus (HCV) patients during viral clearance is unclear and warrants investigation.

METHODS

A prospective study including 747 consecutive chronic hepatitis C (CHC) patients, of whom 546 had completed a course of anti-HCV therapy and underwent pre-, peri- and post-therapy surveys for anthropomorphic, viral, metabolic and hepatic profiles and adiponectin levels, was conducted in a tertiary care center.

RESULTS

Multivariate analyses indicated associations of sex, triglyceride levels and hepatic steatosis with adiponectin levels and of triglyceride levels and interferon λ3 (IFNL3) genotype with homeostasis model assessment-estimated insulin resistance (HOMA-IR) levels before anti-HCV therapy. In patients with a sustained virological response (SVR; n = 455), at 24 weeks post-therapy, sex, BMI, aspartate aminotransferase to platelet ratio index (APRI), HOMA-IR and steatosis were associated with adiponectin levels, and IFNL3 genotype was associated with HOMA-IR levels. GEE analysis demonstrated that SVR affected longitudinal trends in adiponectin levels. Compared with pre-therapy levels, adiponectin and APRI levels decreased 24 weeks post-therapy in SVR patients, regardless of baseline insulin resistance (IR). However, HOMA-IR levels decreased in SVR patients with baseline IR but increased in those without baseline IR. Compared with controls, immunohistochemical studies showed that pre-therapy CHC patients had higher hepatic adiponectin expression associated with hepatic fibrosis.

CONCLUSIONS

During HCV infection, adiponectin may affect insulin sensitivity through triglycerides. After viral clearance, adiponectin levels were directly associated with insulin sensitivity and decreased upon improved hepatic fibrosis; with a link to the IFNL3 genotype, insulin sensitivity improved only in patients with baseline IR.

The Evolving Interplay among Abundant Adipokines in Patients with Hepatitis C during Viral Clearance

How hepatatitis C virus (HCV) infection affects the interplay among abundant adipokines in the host remains unclear. A prospective study was conducted with 450 consecutive genotype 1 (G1) and G2 HCV patients who completed a course of anti-HCV therapy and underwent pre-therapy and 24-week post-therapy surveys to assess various profiles and levels of abundant adipokines, including leptin, adiponectin, and plasminogen activator inhibitor-1 (PAI-1). Before anti-HCV therapy, multivariate analyses showed gender to be associated with leptin and adiponectin levels, and BMI with leptin and PAI-1 levels. Among patients with a sustained virological response (SVR, n = 372), associations at 24 weeks post-therapy were as follows: gender and BMI with all adipokine levels; hepatic steatosis and aspartate aminotransferase to platelet ratio index with adiponectin levels; and HOMA-IR and HCV genotype with PAI-1 levels. Paired t-tests revealed increased post-therapeutic PAI-1 levels in G1 SVR patients and decreased adiponectin levels in all SVR patients compared to pre-therapeutic levels. HCV infection may obscure associations between abundant adipokines and metabolic/hepatic profiles. In SVR patients, a higher hierarchical status of PAI-1 versus adiponectin in affecting glucose metabolism was noted at 24 weeks post-therapy. Such genotype-non-specific adiponectin decreases and G1-specific PAI-1 increases warrant careful follow-up of HCV patients after SVR according to viral genotype.